L25 - Tumor Immunology

Question 1

types of tumor antigens

Answer 1

• mutated versions of normal proteins that are unrelated to the phenotype (passenger mutations)
• mutated versions of normal proteins that are related to the phenotype (TSGs or oncogenes)
• products of genes that are normally expressed at low levels and to which immunological responses are present but that are overexpressed in tumor cells
• proteins encoded by oncogenic viruses

Question 2

immune mechanisms against tumors

Answer 2

• CTLs
• NK Cells
• Antibodies
• Macrophages

Question 3

tumor strategies to escape immune system

Answer 3

• Low Immunogenecity: tumor cells do not express adhesion molecules, tumor-specific antigens, MHC I, or co-stimulatory molecules (B7)
• Antigenic Modulation: mutations to antigens that may not be recognized by immune system
• Immunosuppression: secretion of factors that suppress immune system (TGF-B)

Question 4

lymphokine activated killer (LAK) cells

Answer 4

• Isolate and culture peripheral blood lymphocytes with IL-2
• Natural killer cells will proliferate
• Reintroduce LAK cells into patient with additional IL-2

Question 5

tumor infiltrating lymphocytes

Answer 5

• Isolate and culture lymphocytes from the affected tissue
• Culture in presence of tumor cells and IL-2
• Reintroduce TILs into patient with additional IL-2